Mikhail Ivanovich Budyko (1920–2001) was a Belorussian meteorologist and physicist, as well as a pioneer in the specialized field of physical climatology. He was the author of the 1956 book Heat Balance of the Earth’s Surface. In this work, he used the principles of physics to explain, as no one had done before, how energy from the Sun is absorbed and then radiated back into the atmosphere by the Earth. Budyko’s research led him to become concerned about climate change, and he was one of the first to realize that a build-up of carbon dioxide created by human industry was causing the atmosphere to warm up. He predicted that by 2070 the average temperature on Earth would be 6.3°F (3.5°C) higher than 1950 temperatures. Budyko was also one of the first to predict that a nuclear winter would result from a nuclear war.